42results about How to "Various control methods" patented technology

The invention discloses a modified Trim 21 (delta Trim 21)-based target protein degradation control system, which takes a modified protein delta Trim 21 degradation system as a basis, takes blue light, abscisic acid, Danoprevir and / or MK-5172 as inductors, controls the combination of target protein and delta Trim 21 by introducing and modifying a controllable protein dimerization system on the basis of the modified protein delta Trim 21 degradation system, and improves the target protein degradation control system. The protein targeted degradation capable of being modularly regulated and controlled is carried out. Two regulation and control modules, namely a target protein recognition module and a degradation module based on E3 ubiquitinase, are constructed by splitting and recombining a controllable protein dimerization system and a delta Trim 21 structural domain. The invention also discloses a degradation device comprising the system. The invention also discloses a method for accurately regulating endogenous proteins (degradation of proteins related to tumorigenesis) by using the programmable regulation type modular protein degradation device, so as to achieve the effect of specifically killing tumors. The invention also provides a eukaryotic expression vector and a regulation method of the programmable regulation type protein targeted degradation device.

The invention discloses a light-operated reconfigurable metasurface for full-space terahertz wave beam regulation and control, solves the problem of how to provide ubiquitous full-space wave beam coverage for multi-user wireless communication application, and belongs to the field of artificial electromagnetic metamaterials. The super subunit comprises N super subunits which are arranged periodically, each super subunit comprises 4 * 4 identical coding units, corresponding codes are '0' and '1' respectively when illumination exists or not, and the phase response difference of the two coding units at 0.7 THz is 180 degrees. Each super subunit comprises five layers, the third layer is used for switching between reflection and transmission, when vanadium dioxide is in a medium state, the super surface is in a transmission mode, and when vanadium dioxide is in a metal state, the super surface is in a reflection mode. The first layer, the second layer, the fourth layer and the fifth layer are used for controlling the amplitude and the phase of the total-space terahertz wave, the conductivity of the photosensitive silicon pattern is changed under excitation of light with different intensities, the phase of the total-space terahertz wave beam is effectively modulated, and one-bit terahertz information coding is achieved.

The invention discloses a sensorless control method for a high-speed low-carrier-ratio permanent magnet synchronous generator. The method comprises the following steps: firstly, building a double-loop control system of a controlled permanent magnet synchronous generator comprising a current inner loop and a bus voltage outer loop under the condition of high speed and low carrier wave ratio, selecting an MRAS control strategy as a sensorless control strategy, introducing the MRAS control strategy into the double-loop control system, adjusting parameters of the MRAS control strategy, and controlling the current inner loop and the bus voltage outer loop of the controlled permanent magnet synchronous generator; the double-loop control system is enabled to operate stably; and designing parameters of a controller of the LADRC, and replacing all PI control in a double-loop control system with the LADRC to obtain the sensorless control method of the high-speed low-carrier-ratio permanent magnet synchronous generator based on the LADRC and the MRAS. According to the method, constraint conditions such as high rotating speed, low carrier wave ratio and sensorless control are comprehensively considered, the motor control model when the permanent magnet synchronous motor is used as the generator is constructed, parameter design is carried out in combination with PI control, and a more economical and feasible solution is provided.

The invention relates to the technical field of rectification, in particular to a balanced full-automatic separation control method for a rectifying tower system, the rectifying tower system comprises a rectifying tower I. The control method comprises the following steps: carrying out material balance control and gas-liquid balance control on the rectifying tower I. The gas-liquid balance control is used for controlling the reflux quantity of a material refluxed into the rectifying tower I; the material balance control comprises the following steps: detecting the actual feeding flow of the rectification tower I and the actual liquid level value of a first reflux tank corresponding to the rectification tower I, and calculating and controlling the flow of the material extracted from the tower top of the rectification tower I in real time by combining the set value of the component extracted from the tower top of the rectification tower I and the density of the component extracted from the tower top. Through the preparation method, the stability and the efficiency of a rectifying tower system are improved, and the energy consumption cost and the product volatility problem are reduced.

The invention discloses a virtual shooting prop control method and device, equipment and a storage medium, and relates to the technical field of computers. The method comprises the following steps: displaying a three-dimensional virtual environment, wherein the three-dimensional virtual environment comprises a first virtual object holding a first virtual shooting prop; after a first virtual object picks up a first virtual accessory in a three-dimensional virtual environment, the first virtual accessory is assembled for a first virtual shooting prop, the first virtual accessory is used for adjusting attribute parameters of bullet elements of the first virtual shooting prop, and the bullet elements are minimum shooting units released by single use of the first virtual shooting prop; the first virtual accessory supports and is assembled on a plurality of different types of virtual shooting props; and in response to a use operation for the first virtual shooting prop, controlling the first virtual shooting prop to release the bullet elements to the three-dimensional virtual environment based on the adjusted attribute parameters of the bullet elements. According to the mode, the control mode of the virtual shooting prop is enriched.

The present invention provides a pneumatically controlled high-pressure variable flow control valve, which mainly solves the technical problems of poor flow resistance stability, weak structural interchangeability, large action response dispersion, and disadvantageous mass production of existing variable flow control valves. The control valve of the present invention comprises a valve body, a main valve assembly and a secondary valve assembly arranged in the valve body; the main valve assembly is composed of 4 main valves with the same structure, and the secondary valve assembly is composed of 2 secondary valves with the same structure; the 4 main valves are perpendicular to the central axis of the valve body, and the 4 main valves are grouped in pairs, and the two main valves in each group are located in the same circumference of the valve body, and the central axes of the 4 main valves are located on the same plane or parallel to each other. There are 2 outlets on the valve body, and the medium outlets of the two main valves located on the coaxial side of the central axis of the valve body share the same outlet. The control valve of the present invention has a compact overall structure and a small volume, and the various components have strong interchangeability, which is suitable for mass production.

The invention belongs to the technical field of photonic crystals, and particularly relates to a photonic lattice capable of cutting boundaries in various modes and a method for generating a boundary state. In order to provide crystal lattices with a larger existence range, the evanescent coupling straight waveguides comprise a plurality of uniformly distributed crystal lattice points, the evanescent coupling straight waveguides are arranged on the crystal lattice points, every three crystal lattice points form a primitive cell, and the three crystal lattice points in each primitive cell form an equilateral triangle. The interfaces on the two sides of the evanescent coupling straight waveguide are arranged to be one or two of an alpha-zigzag shape, a beta-zigzag shape and a beam shape. According to the method, construction is simple, various boundaries can be cut, and two different types of boundary states are supported.

The invention provides a blast furnace gas main pressure regulating system for a coke oven. The regulating system comprises a regulating device, a dispersing device, a monitoring device and a control device. The regulating device is arranged on a first pipeline and is used for regulating the gas transmitted from the blast furnace to the coke oven. The dispersing device is arranged on a second pipeline and is used for dispersing the gas in the first pipeline. The monitoring device is arranged on the first pipeline and is used for monitoring the gas pressure of the first pipeline. The control device is electrically connected with the regulating device and is used for controlling the opening and closing of the regulating device. The invention uses a DCS system configuration to pre-close a regulating valve before pressure fluctuations to stabilize the pressure. The operation is simple, safe and reliable. The pressure of the gas entering the coke oven is stable and the safety of the coke oven is ensured. The button for controlling the coke oven is automatically put into operation through a DCS screen control panel. The control is fully automatic. The gas after the pressure stabilization reduces the impact on the regulating valve, thereby increasing the service life of the regulating valve and reducing the production cost.

The utility model discloses a multi-element accurate proportioning low-temperature brimstone furnace control system, which mainly comprises a central controller, and a data acquisition unit, a fan driving unit, a molten sulfur control unit, a metering pump control unit, an atomization control unit, an ignition control unit, a hearth positive and negative pressure protection unit and a brimstone furnace high and low temperature protection unit which are connected with and controlled by the central controller. The sulfur combustion furnace system automatically and accurately distributes air and sulfur according to the squeezing amount or the flow, the stoving intensity and the like, and the problems that due to the fact that an existing sulfur combustion furnace system is inaccurate in air distribution and sulfur distribution, combustion is insufficient, sublimed sulfur is much, and technological indexes are unstable are solved.

The invention relates to a method for enhancing the hydrogen evolution reaction efficiency of a semiconductor photocatalyst through an electric field, belongs to the technical field of photochemistry, and particularly relates to a photochemical analysis technology. Aiming at the urgent need of studying the regulation effect of an electric field on photocatalytic HER, the uniform and parallel electric field perpendicular to the electrode plate is formed by applying the bias voltage, separation of photo-generated carriers of catalyst particles is promoted under the action of Coulomb force, the photocatalytic reaction efficiency is improved, and good practical application value is achieved.

The utility model provides a sound control electric ceramic cooker. The sound control electric ceramic cooker comprises a cooker body assembly, a power supply assembly and a remote control assembly, a heating piece is arranged in the furnace body assembly; the power supply assembly comprises a power supply part, a voice processor and a controller, the voice processor is integrated in the controller, and the power supply part is electrically connected with the controller and the heating part; the controller is electrically connected with the heating piece; the remote control assembly is in signal connection with the controller. Voice control can be achieved, the two hands of a user can be liberated, the control mode of the electric ceramic cooker is more diversified, the cooking efficiency and the user experience are improved, meanwhile, the voice processor and the controller are both arranged on the power source assembly and are far away from the heating piece, operation of the voice processor and the controller cannot be affected when the heating piece conducts heating for cooking, and the user experience is improved. The voice processor and the controller are prevented from being damaged by a high-temperature environment, and the service life of the product is prolonged.

The invention relates to the technical field of brakes, and provides a power-on and power-off laminated brake which comprises a power-on speed reduction unit and a power-off braking unit which are coaxially connected and laminated. The power-off brake unit comprises a power-off yoke, a first armature and a first brake disc which are sequentially arranged in the axial direction. The power-on speed reduction unit comprises a power-on magnet yoke, a second armature and a second brake disc, the second armature is connected with the second brake disc, and a brake spring is connected between the power-on magnet yoke and the second armature in an abutting mode; and the rotating speed of the motor shaft is adjusted by controlling the power-on and power-off states of the power-on yoke and the power-off yoke. The brake has the function of reducing the speed of the motor shaft and also has the maintaining function, and in the speed reducing process, the braking speed reducing torque can be adjusted by controlling the voltage.

The application belongs to the technical field of air conditioners and heat management systems, and particularly relates to an integrated heat pump air conditioner and heat management system and a control method thereof, wherein the integrated heat pump air conditioner and heat management system comprises a refrigerant circulation system, a refrigerant liquid circulation system, a first heat management system and a second heat management system. The refrigerant circulation system, the refrigerant liquid circulation system, the first heat management system and the second heat management system provided by the application can ensure the heating, refrigeration, dehumidification and demisting and other functions and comfort of the vehicle air conditioner system, fully meet the needs of users, and meet the requirements of energy saving and consumption reduction, easy assembly, easy maintenance, good durability, high reliability and light weight, and the control method is intelligent, perfect and reasonable. In addition, the main scene used by the application has the characteristics of typicalization, simplification and rationalization, is conducive to the optimal design of the six-way valve and the eight-way valve, and thus the target of reducing water resistance and system operation noise is achieved.

The invention relates to the technical field of cross-linking suspension control in the high-voltage cable production process, in particular to a cross-linking machine control suspension tool which comprises a tool body, annular sinking grooves are symmetrically formed in the upper end and the lower end of the tool body, and an upper adjusting ring is movably assembled in the annular sinking groove in the upper end of the tool body through an upper bearing. According to the cross-linking machine control suspension tool, by controlling the amplitude of a wire core, the quality of the wire core can be effectively improved, and the cable qualification rate is increased; the size of a transition hole in the tool body can be changed through an outer side stability control mechanism arranged on the outer sides of the upper adjusting ring and the lower adjusting ring in the vertical direction, so that the tool body can be suitable for all middle and high voltage cable models; the cable is extruded from two sides in different directions, so that the amplitude of the cable is reduced, the stability in the suspension process is improved, and the control directions are more diversified.

The present invention discloses a drainage system based on a municipal road combined pipe network, the drainage system comprising: a combined branch pipe; an interception part, the interception part having an inlet and a first outlet, the inlet being connected to the sewage branch pipe, the first outlet being connected to the combined branch pipe, a first hydraulic switch being arranged to control water flow through the first outlet, and a diversion facility being arranged on the municipal combined pipe, the diversion facility having an inlet, a third outlet and a fourth outlet; the present invention arranges the interception part, in rainy days, the first outlet of the interception part is closed, at this time rainwater flowing into the rainwater inlet is merged into the combined branch pipe, to avoid the sewage and rainwater mixing; in sunny days, the first outlet of the interception part is opened, at this time, the domestic sewage transported by the combined branch pipe flows into the sewage treatment facility via the combined branch pipe, the municipal combined pipe and the diversion facility, the diversion of rainwater and sewage is realized in the unit area, to avoid the sewage and rainwater mixing, the combined branch pipe can achieve multiple uses of one pipe, and the existing pipe network system is not greatly modified, the modification cost is low, and the application range is wide.

The invention belongs to the technical field of electric power tools, and discloses a new-energy multifunctional ultrahigh-pressure hydraulic pump which comprises a motor, a hydraulic clamp, a hydraulic pump body, an electromagnetic reversing valve, a pressure sensor, a master control module, a manual switching valve and a high-pressure oil pipe. The control system is characterized by further comprising operation keys, a liquid crystal display module, a motor driver, an air switch, a battery bin, a battery and a remote controller, the electromagnetic directional valve comprises a high-pressure electromagnetic valve and a low-pressure electromagnetic valve, and the pressure sensors comprise a high-pressure pressure sensor and a low-pressure pressure sensor. The master control module comprises a core control unit MCU, an AD analog sampling module and an I / O driving amplification module. The high-altitude crimping system has the following main beneficial technical effects that during high-altitude crimping operation, the control sight is clear, the noise is low, no tail gas is discharged basically, the crimping quality is controllable and visible, the control modes are diversified, and construction data can be stored for a long time so as to be convenient for subsequent calling and use.

The invention relates to the technical field of railway vehicles, in particular to a controllable elastic wheel for a railway vehicle, which comprises a transverse shaft and an external mounting ball head axially fixed on the outer side of the transverse shaft, and an external mounting seat is movably assembled on the outer side of the external mounting ball head on the outer side of the transverse shaft. According to the controllable elastic wheel for the railway vehicle, the split type wheel design is adopted, and noise transmission between the wheel and the axle is reduced; by adopting the design of the annular outer wheel, the vibration reduction area of the wheel can be increased, and the vibration reduction effect is improved; the inner mounting base connected with the frame of the railway vehicle is fixedly assembled on the outer side face of the transverse shaft, and the electric control type magnetic control supporting rod on the outer side of the inner mounting base is connected with the outer assembling disc, so that the angle of the whole wheel is controlled, wheel steering is facilitated, and adaptability is improved.

This invention provides a superconducting excitation device and method, comprising: a superconducting tape; the superconducting tape includes a first superconducting tape and a second superconducting tape; one end of the long side of the first and second superconducting tapes is connected, and the other end is not connected; the superconducting tape is connected to a superconducting load to form a closed loop, a first terminal is connected to one end of the superconducting load, and a second terminal is connected to the other end of the load; a transmission current flows into the first superconducting tape through the first terminal and flows out from the second terminal, with the transmission currents in opposite directions on the first and second superconducting tapes; when the superconducting tape is placed in a changing magnetic field, when the transmission current is greater than the superconducting load current and the direction of the transmission current is the same as the direction of the load current, under the action of the opposite-direction transmission currents on the first and second superconducting tapes, the magnetic flux of the changing magnetic field links with the closed loop, thereby increasing the current of the superconducting load, so as to regulate the current of the superconducting load through the linked magnetic flux. This invention can achieve high-precision regulation of the superconducting load current.

The application provides a traffic signal lamp intelligent regulation system, and relates to the technical field of traffic regulation.The system comprises a traffic information collection unit and an upper computer software system;by fusing modern frontier technologies such as the Internet of Things, big data and geomagnetic field measurement, and combining scientific theories such as automatic control theory, operations research and artificial intelligence, a traffic signal lamp self-adaptive control system based on period time expansion is constructed, and the green light release time is automatically adjusted according to the real-time arrival condition of the traffic flow at the intersection.

A self-suction physiotherapy instrument comprises an air bag, an outer cover, an inner chamber, a main control circuit board and a flexible circuit board, a cover top plate in the outer cover is connected with the bottom of the air bag, the top of the air bag is connected with the main control circuit board, the periphery of the cover top plate is connected with a cover top opening of a cover side wall extending downwards, and the top of the inner chamber is connected with the cover top plate in a sealed mode. The chamber bottom is connected with the flexible bottom layer in a sealed mode, the top face of the flexible bottom layer makes contact with the bottom face of the flexible circuit board, the flexible circuit board and the battery are both located in the inner chamber, and the chamber side wall and the cover top plate are provided with side air holes and air suction holes respectively. An outer partition cavity formed between the chamber side wall and the cover side wall sequentially passes through the side air holes, the chamber inner cavity and the air suction holes and then communicates with the interior of the air bag, and the main control circuit board is in circuit connection with the battery and the flexible circuit board. The design is high in simplicity degree and easy to carry and use.

The present invention discloses a drainage system based on a municipal road combined pipe network, the drainage system comprising: a combined branch pipe; an interception part, the interception part having an inlet and a first outlet, the inlet being connected to the sewage branch pipe, and the first outlet being connected to the combined branch pipe; a buffer part, being connected to the interception part through a second outlet; a diversion facility, which is arranged on the municipal combined pipe, and the diversion facility having an inlet, a third outlet and a fourth outlet; the present invention arranges the interception part, in rainy days, the first outlet of the interception part is closed, at this time the rainwater flowing into the rainwater inlet is merged into the combined branch pipe, so as to avoid the mixing of sewage and rainwater; in sunny days, the first outlet of the interception part is opened, at this time the domestic sewage transported by the combined branch pipe flows into the sewage treatment facility through the combined branch pipe, the municipal combined pipe and the diversion facility, so as to realize the diversion of rainwater and sewage in the unit area, so as to avoid the mixing of sewage and rainwater, and the combined branch pipe can realize multiple uses of one pipe, and the modification of the existing pipe network system is not large, the modification cost is low, and the application scope is wide.

The invention belongs to the field of data acquisition, regulation and control of heat supply network secondary network equipment, and provides a heat supply network equipment communication protocol design method based on a LoRa technology, which comprises the steps of communication channel and communication frame format determination and communication process division. According to the invention, the network address is divided into the network number, the group number and the intra-group address number, so that the networking requirement of a large-scale network is met, and the communication efficiency is improved through packet communication; communication channels are divided into different functional groups, so that the communication capacity is improved; the flexibility of the network nodes is improved by designing networking and network quitting processes of the nodes; by designing a data type code and a data field, the regulation and control effect is improved; by designing a communication quality test frame, the problem of LoRa gateway site selection is solved, and the networking difficulty is reduced; by designing the firmware upgrading frame, the firmware upgrading of the node through the LoRa network is realized; and by adopting a data encryption technology, the network security is improved.

The invention discloses a virtual control method and device for smart home equipment, a sofa and a storage medium. The method is applied to the sofa, a projector is arranged in the sofa, and the method comprises the following steps: in response to projection operation, determining a projection position, and controlling the projector to project an equipment layout map at the projection position; in response to a selection operation on a first smart home device in the device layout map, controlling a projector to project a virtual control panel corresponding to the first smart home device at a projection position; and in response to a control operation on the virtual control panel, sending a control instruction corresponding to the control operation to the first smart home device so as to control the first smart home device to execute the first function. Through the virtual control method and device of the smart home device, the sofa and the storage medium, a user can remotely control the smart home device on the sofa, the control modes of the smart home device are enriched, the control operation is simpler and more convenient, and the use experience of the user is improved.

The invention provides an electric lifting cup stand based on an LIN (Local Interconnect Network) bus protocol, which comprises a cup stand main body and a lifting structure capable of lifting in the cup stand main body, and further comprises a control module and a driving module for driving the lifting structure to lift, the control module can be in communication connection with a vehicle-mounted terminal system based on an LIN bus protocol, and the control module is in communication connection with the driving module based on the LIN bus protocol. The control module is used for receiving a cup stand lifting signal sent by a vehicle-mounted terminal system and sending an LIN communication signal to the driving module so as to control the working state of the driving module. Overall wiring can be simplified, actual operation, use and fault discovery of a user are facilitated, and the use experience of the user is greatly improved.

The present application relates to rectification technical field, particularly to a kind of rectification tower system balance full-automatic separation control method, rectification tower system includes rectification I tower, control method includes to rectification I tower is carried out material balance control and gas-liquid equilibrium control, gas-liquid equilibrium control is used to control the amount of backflow of material backflow to rectification I tower;The material balance control includes: detecting the actual feed flow of rectification I tower and the actual liquid level value of the first reflux tank corresponding to rectification I tower, in combination with the overhead take-off component set point of rectification I tower and the overhead take-off component density, the overhead take-off material flow of rectification I tower is calculated and controlled in real time.By the method, the stability and efficiency of rectification tower system are improved, and the energy consumption cost and the volatility problem of product are reduced.

The invention provides a control method, system and device for external interaction, a medium and a vehicle. The control method comprises the steps that one or more of in-vehicle gestures, in-vehicle voice, central control screen data and terminal data are acquired; according to the in-vehicle gesture, the in-vehicle voice, the central control screen data and the terminal data, the control type is judged, wherein the control type comprises active control and automatic control; if the control is active control, generating display content according to the input content, and displaying the display content on an external interaction screen; and if the control is automatic control, comparing with a preset database, generating corresponding display content according to the corresponding scene data, and displaying the corresponding display content on the external interaction screen. And if the driver wants to control in the vehicle driving process, the driver can control through gestures or voice, so that the driver is not distracted. Other passengers in the vehicle can control the central control screen through one of gestures, voices, the central control screen and the terminal, so that the control modes of the external interaction screen are diversified.

An improved leachate treatment integrated device for a garbage transfer station belongs to the technical field of sewage treatment and garbage leachate treatment, and is characterized in that a water producing pump, a water producing tank, a fan, a dosing device and an electric control cabinet are arranged in an equipment room. The internal structure is compact, functions are complete, and operation regulation and control are intelligent. The system regulation and control modes of water inlet, backflow, dosing, cooling and the like in the equipment are diversified, the biochemical treatment efficiency can be effectively improved, and through point water inlet, multi-stage AO, multi-point backflow, air pipe communication, intelligent control and the like, the addition amount of an external carbon source and the aeration air volume of a fan can be effectively reduced, and the total nitrogen can be efficiently removed, so that the energy conservation, consumption reduction, cost reduction and efficiency improvement of a project are realized; the device is low-carbon equipment in the field of leachate treatment.

The present invention discloses a high-pressure air heater, including a mounting seat, on which a heater body and a control component are arranged; the heater body includes at least two heating modules I distributed in the horizontal direction, and each heating module I includes at least two heating modules II distributed in the vertical direction; each heating module II is electrically connected to the control component, so that the heater body is divided into at least four heating zones, and each heating zone can be individually controlled by the control component. The high-pressure air heater disclosed by the present invention has multiple heating zones, and can be individually controlled, so that the heating zone control is more accurate and the heating zone is highly targeted.

The utility model provides a pneumatic regulating valve connecting rod device which comprises a mounting box and a driving plate, positioning rods are symmetrically connected to the middle of the interior of the mounting box, positioning holes are correspondingly formed in the positions, opposite to the positioning rods, of the surface of a movable plate, movable grooves are symmetrically formed in the two ends of the movable plate, and the driving plate is movably connected into the movable grooves through bearings. Meanwhile, penetrating openings are symmetrically formed in the side, away from the pneumatic actuator, of the mounting box, limiting rods are fixedly connected into the penetrating openings, the end, away from the movable plate, of the driving plate is movably connected with one end of a driven plate through a bearing, the other end of the driven plate is movably connected with a push plate through a bearing, and limiting grooves are correspondingly formed in the positions, opposite to the limiting rods, of the surface of the driven plate; and the push plate is slidably connected into a through groove formed in the fixed plate. Through the cooperation of the pneumatic actuator, the moving plate, the connecting rod assembly and the clamping plate, the connecting rod device can correspondingly fix the valve rod, and then the probability that the valve rod accidentally moves can be reduced.

The utility model provides a variable valve timing system of a motorcycle engine, and belongs to the technical field of motorcycles. The problem of how to ensure the compact structure of the engine while ensuring normal oil supply and lubrication is solved. According to the variable valve timing system of the motorcycle engine, the motorcycle engine comprises a cylinder head which is provided with an oil supply channel and internally and rotatably connected with a cam shaft, a cavity is formed in the cam shaft, and a plurality of oil outlet holes are formed in the outer wall of the cam shaft in the axial direction; the variable valve timing system comprises a rotor fixed to one end of the cam shaft through a bolt and a shell arranged outside the rotor in a sleeving mode, the bolt is in a rod shape and divides an inner cavity of the cam shaft into an oil conveying cavity and a lubricating cavity in the axial direction, and the oil conveying cavity is communicated with an oil supply channel and an inner cavity of the shell. A flow dividing channel for communicating the oil conveying cavity with the lubricating cavity is formed in the bolt, and the lubricating cavity communicates with the oil outlet holes. The variable valve timing system of the motorcycle engine can ensure that the structure of the engine is compact while normal oil supply and lubrication are ensured.